package dome3;

public class Computer {
    public void opean(){
        System.out.println("开机");
    }
    public void close(){
        System.out.println("关机");
    }
    public void useUsbDecvise(USB usb) {
        usb.opeanDevice();

        if (usb instanceof Mouse) {
            Mouse mouse = (Mouse) usb;
            mouse.click();
        } else {
            keyboard key = (keyboard) usb;
            key.input();
        }
        usb.closeDevice();
    }
}
